Preheat the oven to 350. Line an 8 or 9-inch square baking dish with foil and spray the foil with non-stick spray.

In a bowl, combine the oats, almonds, flour, brown sugar, salt,
baking powder, cinnamon and nutmeg. Sprinkle the oat mixture with the
almond extract. Add the butter and egg yolks and use a pastry cutter to
incorporate the butter and eggs into the oat mixture until it's coarse
and crumbly.

Scoop half of the mixture into the baking dish and press firmly
against the bottom. (You may think the mixture is too dry, but it will
work.) Spread the jam evenly over the crust (warm the jam slightly if
it's difficult to spread). Add the fruit or berries. Sprinkle the
remainder of the oat mixture over the fruit like a crumble topping.

Bake for 30-35 minutes, until golden brown. Cool for 1 hour in
the pan on a wire rack, then lift the foil out of the pan and cool
completely before cutting into squares.